Attention Deficit Hyperactivity Disorder Traits Research Articles

Initial Impact of the COVID-19 Outbreak on ADHD Symptoms Among University Students in Japan.

The coronavirus disease 2019 pandemic and its associated societal responses are anticipated to have wide-ranging effects on youth development and mental health. Depression, anxiety, and attention deficit hyperactivity disorder (ADHD) are the three most common mental health problems among university students. Many factors that can threaten mental health during the outbreak affect these three conditions, as well as sleep conditions, in undergraduate students. Thus, determining how these abrupt changes in students' circumstances impact their mental health is very important from a public health perspective. We investigated the usual conditions and changes in ADHD symptoms during the outbreak, in relation to depressive and sleep-related symptoms among undergraduate students. A total of 252 students, primarily juniors, completed the online survey. The results showed that 12% of the students exceeded the cut-off score of the ADHD questionnaire before the pandemic. Approximately 6%-21% of the university students, especially those with ADHD traits, rated their ADHD behaviors as worse during the outbreak than that before the outbreak. Female students and undergraduates with ADHD traits are more susceptible to experiencing further deterioration of ADHD (inattention) symptoms during the pandemic. In cases where it is difficult to intervene with ADHD symptoms, approaching circadian rhythm or depression will be of considerable clinical use.

Illness-perception in adolescent attention-deficit/hyperactivity disorder: A qualitative study.

Adolescents with attention-deficit/hyperactivity disorder (ADHD) experience aspects of their lives in diverse ways. They often have more energy and creativity which are positive traits of ADHD, while their inability to control their actions in academic or social spheres may cause feelings of inadequacy. To explore illness-perception, including emotional experiences, in adolescent ADHD. Using convenience sampling, 12 adolescent participants, eight boys and four girls, diagnosed with ADHD, were included. Participants followed up at Weskoppies Tertiary Psychiatric Hospital's child-and-adolescent outpatient clinic. This qualitative study used semi-structured question guides to conduct interviews that allowed participants to actively construct their knowledge of their disorder. Maintaining a phenomenological perspective, thematical analysis of data was done. Adolescents' perceptions of their ADHD could be placed into three categories. 'Negative self-perception in ADHD' represented adolescents' descriptions of 'inability' and 'lack of control' over their cognitive processes, behaviour, emotions, and restlessness. Adolescents perceived 'feeling judged by others', amplified self-stigmatisation and discrimination. This antagonistic environment caused conflict between their self-perception and others' perception of them, further intensifying feelings of 'not being normal'. The theme 'self-empowerment strategies', included controlling external stimuli, accepting support from others, and personalised learning strategies. Adolescents with ADHD struggle with cognitive, behavioural, and emotional control, and frequently experience stigmatisation and discrimination. They often learn to rely on self-taught coping strategies. This research grants perspective to educators and clinicians on experiences of adolescents with ADHD, and identifies the need to address stigmatisation. It recognises the value of personalisation of coping methods.

Association between early-childhood exposure to perfluoroalkyl substances and ADHD symptoms: A prospective cohort study

There is evidence that exposure to perfluoroalkyl substances (PFAS) is associated with attention-deficit/hyperactivity disorder (ADHD) symptoms. Previous studies have focused on prenatal exposure to PFAS, and only few studies have examined the associations of early-childhood exposure, especially at low exposure levels. This study explored the association between early-childhood exposure to PFAS and ADHD symptoms later in childhood. In 521 children, we measured the serum levels of six PFAS in peripheral blood at the ages of 2 and 4 years, including perfluorooctanoate (PFOA), perfluornonanoicacid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnDA), perfluorohexane sulfonic acid (PFHxS), and perfluorooctane sulfonate (PFOS). The ADHD Rating Scale IV (ARS) was utilized to measure ADHD traits at 8 years of age. We explored the relationship between PFAS and ARS scores using Poisson regression models after adjusting for potential confounders. Levels of exposure to individual PFAS and the summed value were divided into quartiles to examine possible nonlinear relationships. All six PFAS exhibited inverted U-shaped curves. Children in the 2nd and 3rd quartile levels of each PFAS showed higher ARS scores than those in the1st quartile level. Below the 3rd quartile of the summed levels of six PFAS (ΣPFAS), a doubling of the ΣPFAS was associated with an 20.0 % (95 % CI: 9.5 %, 31.5 %) increase in ADHD scores. However, at the age of 4 years, none of the evaluated PFAS exhibited linear or nonlinear associations with the ARS scores. Thus, school-aged children may be vulnerable to the neurotoxic effects of exposure to PFAS at age 2 that contribute to ADHD, particularly at low to mid-levels.

Hyperfocus symptom and internet addiction in individuals with attention-deficit/hyperactivity disorder trait.

Hyperfocus symptom is the intense concentration on a certain object. It is a common but often overlooked symptom in those with attention-deficit/hyperactivity disorder (ADHD). Hyperfocus disrupts attention control and results in a focus on inappropriate behaviors. It allows individuals to focus on internet use and make them use internet excessively. This excessive internet use can lead to an addiction. This study investigated the status of IA and hyperfocus, the mediation effect of hyperfocus in relation to IA, and the relationship between ADHD subtypes and hyperfocus in those with ADHD symptoms. This web-based cross-sectional study included 3,500 Japanese adults who completed internet-based questionnaires, which included the Adult ADHD Self-Report Scale (ASRS), Internet Addiction Test (IAT), and Hyperfocus Scale (HFS) to assess ADHD symptoms, internet dependence, and hyperfocus symptoms, respectively. The mediating role of HFS in the relationship between ASRS and IAT was assessed by mediation analysis. To analyze the relationship between hyperfocus symptoms and ADHD subtypes, we compared the correlation of HFS with the Inattention and Hyperactive Scores of ASRS. ADHD traits were associated with higher IAT scores (p < 0.001) and higher HFS scores (p < 0.001). Mediation analysis and bootstrap testing showed that HFS significantly mediated the association between ASRS and IAT. Analyses of ADHD subtypes demonstrated that HFS was significantly correlated with the Inattention (R = 0.597, p < 0.001) and Hyperactive (R = 0.523, p < 0.001) Scores. The correlation between HFS and the Inattention Score was significantly higher than that between HFS and the Hyperactive Score (p < 0.001). Our findings suggest that hyperfocus may play an important role in addictive behavior in ADHD as a manifestation of attentional control malfunction.

Exploring the effect of ADHD traits on the moment-to-moment interplay between provocation and aggression: Evidence from dynamic structural equation modeling.

The relation between attention deficit hyperactivity disorder (ADHD) symptoms and aggression is well documented; however, the processes that account for higher levels of aggression associated with ADHD in the course of daily life are little understood. The current study used ecological momentary assessment to explore how ADHD traits relate to individual differences in perceiving provocation from others and the resultant aggressive behaviors; and the strengths of the links between provocation and aggression in the flow of daily life. A dynamic structural equation model was fit using data from a subpopulation of young adults involved in the longitudinal z-proso study (n = 259, median-age 20). Data on provocation and aggression was collected at four quasi-random time periods per day over a 14-day period. Individuals with higher ADHD trait levels reported higher instances of provocation and aggression, with ADHD traits significantly moderating aggression inertia such that those with higher levels of ADHD traits showed greater persistence of aggressive behavior over time. However, ADHD trait levels did not significantly moderate any of the observed cross-lagged effects. Our findings suggest that individuals with higher levels of ADHD traits are at greater risk of exposure to interpersonal interactions involving interpersonal provocation, show higher levels of aggressive behavior in daily life, and find it more difficult to reduce their aggression once triggered. These findings support the importance of targeting factors such as social skills and emotion regulation that may underpin the increased difficulties in interpersonal interactions often experienced by individuals with high levels of ADHD symptoms.

Attention-deficit hyperactivity disorder traits are a more important predictor of internalising problems than autistic traits

Autism Spectrum Disorder (ASD) and Attention-Deficit Hyperactivity Disorder (ADHD) are both linked to internalising problems like anxiety and depression. ASD and ADHD also often co-occur, making their individual statistical contributions to internalising disorders difficult to investigate. To address this issue, we explored the unique associations of self-reported ASD traits and ADHD traits with internalising problems using a large general population sample of adults from the United Kingdom (N = 504, 49% male). Classical regression analyses indicated that both ASD traits and ADHD traits were uniquely associated with internalising problems. Dominance and Bayesian analyses confirmed that ADHD traits were a stronger, more important predictor of internalising problems. However, brief depression and anxiety measures may not provide a comprehensive index of internalising problems. Additionally, we focused on recruiting a sample that was representative of the UK population according to age and sex, but not ethnicity, a variable that may be linked to internalising disorders. Nevertheless, our findings indicate that while ASD and ADHD uniquely predict internalising problems, ADHD traits are a more important statistical predictor than ASD traits. We discuss potential mechanisms underlying this pattern of results and the implications for research and clinical practice concerning neurodevelopmental conditions.

Identifying Attention Deficit Hyperactivity Disorder (ADHD) Children and Effective Teaching Strategies That Develop Their Multiple Intelligences

Many of us sometimes fail or misinterpret ADHD children by not understanding fully their traits and symptoms. As a result, many ADHD children are viewed as marginal students at school since they can’t meet academic standards. Thus, the purpose of this study is to identify ADHD traits and implement effective teaching strategies for ADHD children which can develop their multiple intelligences. Knowing and applying effective methods and strategies for teaching ADHD children are very essential for them to achieve academic success. Therefore, through this research hopefully, teachers can identify ADHD children and implement effective teaching strategies that can develop multiple intelligences for ADHD children optimally. This research is qualitative research with a literature study approach. The results of this research are characteristics of ADHD and effective teaching strategies including assessment and tools that can be used in a classroom that can help to develop 9 multiple intelligences.

Trajectories of emotional and behavioral problems in school-age children with coordination difficulties and their relationships to ASD/ADHD traits

BackgroundAlthough research has demonstrated associations between motor coordination difficulties and psychological problems in school-age children, including emotional and behavioral problems, longitudinal changes in these problems in children with motor coordination difficulties are not fully understood. AimsThe current study aimed to identify patterns in the trajectory of emotional and behavioral problems in school-age children with motor coordination difficulties, and to elucidate the effect of co-existing neurodevelopmental traits on the occurrence and course of these problems. Methods and proceduresUsing the Developmental Coordination Disorder Questionnaire, 773 children were defined as cases with motor coordination difficulties and followed for 4 years, from 6 to 10 years of age. Emotional and behavioral problems were assessed using the Strengths and Difficulties Questionnaire completed by children’s parents or guardians. Outcomes and resultsWe identified four trajectory patterns of emotional and behavioral problems. Children with higher autism spectrum disorder and attention deficit hyperactivity disorder traits were more likely to be assigned to poor prognostic trajectory patterns. Conclusions and implicationsOur findings emphasize the importance of assessing emotional and behavioral problems and co-existing neurodevelopmental traits in children with motor coordination difficulties in early elementary school.

Genetic nurture versus genetic transmission of risk for ADHD traits in the Norwegian Mother, Father and Child Cohort Study

Identifying mechanisms underlying the intergenerational transmission of risk for attention-deficit/hyperactivity disorder (ADHD) traits can inform interventions and provide insights into the role of parents in shaping their children’s outcomes. We investigated whether genetic transmission and genetic nurture (environmentally mediated effects) underlie associations between polygenic scores indexing parental risk and protective factors and their offspring’s ADHD traits. This birth cohort study included 19,506 genotyped mother-father-offspring trios from the Norwegian Mother, Father and Child Cohort Study. Polygenic scores were calculated for parental factors previously associated with ADHD, including psychopathology, substance use, neuroticism, educational attainment, and cognitive performance. Mothers reported on their 8-year-old children’s ADHD traits (n = 9,454 children) using the Parent/Teacher Rating Scale for Disruptive Behaviour Disorders. We found that associations between ADHD maternal and paternal polygenic scores and child ADHD traits decreased significantly when adjusting for the child polygenic score (pΔβ = 9.95 × 10−17 for maternal and pΔβ = 1.48 × 10−14 for paternal estimates), suggesting genetic transmission of ADHD risk. Similar patterns suggesting genetic transmission of risk were observed for smoking, educational attainment, and cognition. The maternal polygenic score for neuroticism remained associated with children’s ADHD ratings even after adjusting for the child polygenic score, indicating genetic nurture. There was no robust evidence of genetic nurture for other parental factors. Our findings indicate that the intergenerational transmission of risk for ADHD traits is largely explained by the transmission of genetic variants from parents to offspring rather than by genetic nurture. Observational associations between parental factors and childhood ADHD outcomes should not be interpreted as evidence for predominantly environmentally mediated effects.

Annual Research Review: Perspectives on progress in ADHD science - from characterization to cause.

The science of attention-deficit/hyperactivity disorder (ADHD) is motivated by a translational goal - the discovery and exploitation of knowledge about the nature of ADHD to the benefit of those individuals whose lives it affects. Over the past fifty years, scientific research has made enormous strides in characterizing the ADHD condition and in understanding its correlates and causes. However, the translation of these scientific insights into clinical benefits has been limited. In this review, we provide a selective and focused survey of the scientific field of ADHD, providing our personal perspectives on what constitutes the scientific consensus, important new leads to be highlighted, and the key outstanding questions to be addressed going forward. We cover two broad domains - clinical characterization and, risk factors, causal processes and neuro-biological pathways. Part one focuses on the developmental course of ADHD, co-occurring characteristics and conditions, and the functional impact of living with ADHD - including impairment, quality of life, and stigma. In part two, we explore genetic and environmental influences and putative mediating brain processes. In the final section, we reflect on the future of the ADHD construct in the light of cross-cutting scientific themes and recent conceptual reformulations that cast ADHD traits as part of a broader spectrum of neurodivergence.

A Mega-analytic Study of White Matter Microstructural Differences Across 5 Cohorts of Youths With Attention-Deficit/Hyperactivity Disorder

BackgroundWhile attention-deficit/hyperactivity disorder (ADHD) has been associated with differences in the structural connections formed by the brain’s white matter tracts, studies of such differences have yielded inconsistent findings, likely reflecting small sample sizes. Thus, we conducted a mega-analysis on in vivo measures of white matter microstructure obtained through diffusion tensor imaging of more than 6000 participants from 5 cohorts. MethodsIn a mega-analysis, linear mixed models were used to test for associations between the fractional anisotropy of 42 white matter tracts and ADHD traits and diagnosis. Contrasts were made against measures of mood, anxiety, and other externalizing problems. ResultsOverall, 6993 participants (ages 6–18 years, mean age 10.62 years [SD 1.99]; 3368 girls, 3625 boys; 764 African American, 4146 non-Hispanic White, and 2083 other race/ethnicities) had measures of ADHD and other emotional/behavioral symptoms (N = 6933) and/or enough clinical data to allow a diagnosis of ADHD (n = 951) or its absence (n = 4884). Both the diagnosis and symptoms of ADHD were associated with lower fractional anisotropy of the inferior longitudinal and left uncinate fasciculi (at a false discovery rate–adjusted p < .05). Associated effect sizes were small (the strongest association with ADHD traits had an effect size of partial r = −0.14, while the largest case-control difference was associated with an effect size of d = −0.3). Similar microstructural anomalies were not present for anxiety, mood, or externalizing problems. Findings held when ADHD cases and control subjects were matched on in-scanner motion. ConclusionsWhile present across cohorts, ADHD-associated microstructural differences had small effects, underscoring the limited clinical utility of this imaging modality used in isolation.

Working memory and reaction time variability mediate the relationship between polygenic risk and ADHD traits in a general population sample

Endophenotypes are heritable and quantifiable traits indexing genetic liability for a disorder. Here, we examined three potential endophenotypes, working memory function, response inhibition, and reaction time variability, for attention-deficit hyperactivity disorder (ADHD) measured as a dimensional latent trait in a large general population sample derived from the Adolescent Brain Cognitive DevelopmentSM Study. The genetic risk for ADHD was estimated using polygenic risk scores (PRS) whereas ADHD traits were quantified as a dimensional continuum using Bartlett factor score estimates, derived from Attention Problems items from the Child Behaviour Checklist and Effortful Control items from the Early Adolescent Temperament Questionnaire-Revised. The three candidate cognitive endophenotypes were quantified using task-based performance measures. Higher ADHD PRSs were associated with higher ADHD traits, as well as poorer working memory performance and increased reaction time variability. Lower working memory performance, poorer response inhibition, and increased reaction time variability were associated with more pronounced ADHD traits. Working memory and reaction time variability partially statistically mediated the relationship between ADHD PRS and ADHD traits, explaining 14% and 16% of the association, respectively. The mediation effect was specific to the genetic risk for ADHD and did not generalise to genetic risk for four other major psychiatric disorders. Together, these findings provide robust evidence from a large general population sample that working memory and reaction time variability can be considered endophenotypes for ADHD that mediate the relationship between ADHD PRS and ADHD traits.

Hyperfocus or flow? Attentional strengths in autism spectrum disorder.

The comorbidity of autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) diagnoses is well established. An ASD diagnosis is associated with elevated ADHD traits and symptoms, as well as strengths in attention. In the ASD literature, attentional strengths have been described as maladaptive (e.g., hyperfocus), in contrast with positive portrayals in the typically developing population (e.g., flow). The objective of this study was to (1) compare profiles of attentional strengths and weaknesses in ASD and ADHD and (2) determine whether attentional strengths in ASD are associated with impairment, poorer cognitive flexibility, and perseveration/perfectionism. In a community sample of 5,744 children and youth, 131 children were reported as having a diagnosis of ASD (mean age 10.3 years) and 346 children were reported as having a diagnosis of ADHD (mean age 10.7 years). We used the Strengths and Weaknesses of Attention-Deficit/Hyperactivity-symptoms and Normal-behaviors (SWAN) rating scale to calculate attentional and hyperactive/impulse control strength and weakness counts and scores. The Autism-Spectrum Quotient Switching factor served as a measure of cognitive flexibility. Impairment was assessed with the Columbia Impairment Scale. We used the symmetry/ordering factor on the Toronto Obsessive-Compulsive Scale as a measure of perseveration/perfectionism. No differences were found between the ADHD and ASD groups in SWAN weakness scores, symptoms, or hyperactive/impulse control strengths; however, autistic children had higher rates of attentional strengths [odds ratio: 5.7, 95% CI (2.8, 11.6), p < 0.0001]. Post-hoc pairwise testing identified four attentional strengths with significantly higher rates in ASD than in ADHD. Attentional strength scores were not associated with impairment or poor cognitive flexibility, but predicted levels of perseveration/perfectionism. The effect of attentional strengths on impairment and cognitive flexibility did not differ between autistic and Control children, but the higher perseveration/perfectionism scores seen in ASD were not found in Control children. ASD is associated with a pattern of attentional strengths that is not found in ADHD Characterizing the full range of attentional abilities in autistic children may explain variability in outcomes such as quality-of-life indicators and identify protective factors, providing targets for strength-based behavioral interventions. The clinical and etiological implications of the subgroup of autistic children with attentional strengths require further investigation.

The relationship between executive function, neurodevelopmental disorder traits, and academic achievement in university students.

Difficulties with executive function have often been identified in individuals with various neurodevelopmental disorders such as Autism Spectrum Disorder (ASD), Attention-Deficit Hyperactivity Disorder (ADHD), and Developmental Co-ordination Disorder (DCD). Additionally, in childhood and adolescence, executive functioning is an important predictor of academic achievement. However, less research has explored these relationships in adult students, and those with a high level of neurodevelopmental disorder traits but no clinical diagnosis. Therefore, the current study aimed to assess whether ASD, ADHD, and DCD traits can predict academic achievement in university students, and whether traits of these neurodevelopmental conditions moderate the relationship between executive function and academic achievement. Both neurotypical students and those with a clinical diagnosis of a neurodevelopmental disorder were able to participate, with the majority being neurotypical. Participants completed four self-report questionnaires and provided a measure of academic achievement based on their university assignment results. Traits of ASD, ADHD, and DCD alone did not predict achievement, however, traits of ADHD and DCD significantly moderated the relationship between executive function and academic achievement. ASD traits did not significantly moderate this relationship. Implications and suggestions for future research are also discussed.

Sensory processing in 16p11.2 deletion and 16p11.2 duplication.

Deletions and duplications at the chromosomal region of 16p11.2 have a broad range of phenotypic effects including increased likelihood of intellectual disability, autism, attention deficit hyperactivity disorder (ADHD), epilepsy, and language and motor delays. However, whether and how sensory processing is affected has not yet been considered in detail. Parents/caregivers of 38 children with a 16p11.2 deletion and 31 children with a 16p11.2 duplication completed the Sensory Behavior Questionnaire (SBQ) and the Child Sensory Profile 2 (CSP-2) along with other standardized questionnaires assessing autistic traits (SRS-2), ADHD traits (Conners 3), anxiety (SCAS-P) and adaptive behavior (VABS-3). SBQ and CSP-2 responses found that sensory processing differences were clearly evident in both 16p11.2 deletion and 16p11.2 duplication, though there was significant variation in both cohorts. SBQ data indicated the frequency and impact of sensory behavior were more severe when compared to neurotypical children, with levels being similar to autistic children. CSP-2 data indicated over 70% of children displayed clear differences in sensory registration (missing sensory input). Seventy-one percent with 16p11.2 duplications were also unusually sensitive to sensory information and 57% with 16p11.2 duplications were unusually avoidant of sensory stimuli. This first detailed assessment of sensory processing, alongside other clinical features, in relatively large cohorts of children with a 16p11.2 deletion and 16p11.2 duplication demonstrates that sensory processing differences have a profound impact on their lives.

Training inhibitory control in adolescents with elevated attention deficit hyperactivity disorder traits: a randomised controlled trial of the Alfi Virtual Reality programme

IntroductionAttention deficit hyperactivity disorder (ADHD) is characterised by significant deficits in attention and inhibition. These deficits are associated with negative sequelae that emerge in childhood and often continue throughout adolescence....

Differential effect of folate metabolic system genetic variants on attention deficit hyperactivity disorder severity

BackgroundAdequate folate level is vital for the synthesis of neurotransmitters, and hence, folate deficiency was related to neurobehavioral disorders like depression, Autism spectrum disorders, and Attention Deficit Hyperactivity Disorder (ADHD). Genetic variants involved in folate metabolism were also reported to affect ADHD traits. We have analyzed the contribution of FOLR1 rs2071010, FOLR2 rs2298444, TCN2 rs1801198, and SHMT1 rs1979277 in the etiology of Indian ADHD probands. MethodsEthnically matched controls (N = 286) and unrelated nuclear families with ADHD probands (N = 221) were recruited following the Diagnostic and Statistical Manual for Mental Disorders (DSM). Traits were assessed using the Conners' Parent Rating Scale-Revised, DSM, and Parental Account of Children's Symptoms criteria. Genetic variants were analyzed by PCR-based methods/TaqMan assay. Genetic association analyses were performed using the UNPHASED. Linkage disequilibrium was calculated using Haploview. Quantitative Trait Analysis was performed to identify the association between genetic variants and trait scores. ResultsParental bias in the transmission of rs1979277 “C” to the ADHD probands was detected. Maternally biased transmission of rs2298444 “G” was also observed. LD between rs2071010-rs2298444 was strong in the control population. Trait scores of the male ADHD probands were higher in the presence of rs2298444 “A” while the behavioral problem was less in the presence of rs1801198 “CC”. In the male probands, studied sites exhibited stronger independent effects, while in the female probands, additive effects between rs2298444-rs1801198 and rs2298444-rs1979277 were observed. ConclusionWe infer that ADHD severity is differentially influenced by genetic variants regulating folate metabolism.

Parsing ADHD With Temperament Traits

Attention-deficit/hyperactivity disorder (ADHD) is common, is costly, and confers substantial risk of chronic poor outcome. It exemplifies the need to better understand variation within psychiatric conditions (heterogeneity) and co-occurrence of different conditions. In particular, ADHD’s broad clinical heterogeneity has required clarification, as subtypes for which there is consensus have not emerged. The outlook for making progress in understanding ADHD heterogeneity is promising, however, when one considers dimensions of trait affectivity, such as surgency and negative affectivity; their constituent lower-order traits, such as irritability; and the integrative function of self-regulation. Several lines of investigation focusing on ADHD and temperament traits (related to emotional regulation and dysregulation) are proving useful. Work in this area has the potential to improve theory, nosology, and clinical assessment in the future.

Gray matter volumetric correlates of attention deficit and hyperactivity traits in emerging adolescents

Previous research has demonstrated reduction in cortical and subcortical, including basal ganglia (BG), gray matter volumes (GMV) in individuals with attention deficit hyperactivity disorder (ADHD), a neurodevelopmental condition that is more prevalent in males than in females. However, the volumetric deficits vary across studies. Whether volumetric reductions are more significant in males than females; to what extent these neural markers are heritable and relate to cognitive dysfunction in ADHD remain unclear. To address these questions, we followed published routines and performed voxel-based morphometry analysis of a data set (n = 11,502; 5,464 girls, 9–10 years) curated from the Adolescent Brain Cognition Development project, a population-based study of typically developing children. Of the sample, 634 and 2,826 were identified as monozygotic twins and dizygotic twins/siblings, respectively. In linear regressions, a cluster in the hypothalamus showed larger GMV, and bilateral caudate and putamen, lateral orbitofrontal and occipital cortex showed smaller GMVs, in correlation with higher ADHD scores in girls and boys combined. When examined separately, boys relative to girls showed more widespread (including BG) and stronger associations between GMV deficits and ADHD scores. ADHD traits and the volumetric correlates demonstrated heritability estimates (a2) between 0.59 and 0.79, replicating prior findings of the genetic basis of ADHD. Further, ADHD traits and the volumetric correlates (except for the hypothalamus) were each negatively and positively correlated with N-back performance. Together, these findings confirm volumetric deficits in children with more prominent ADHD traits. Highly heritable in both girls and boys and potentially more significant in boys than in girls, the structural deficits underlie diminished capacity in working memory and potentially other cognitive deficits in ADHD.

Child ADHD and autistic traits, eating behaviours and weight: A population-based study.

Children with Autism Spectrum Disorder (ASD) and Attention-Deficit/Hyperactivity Disorder (ADHD) have an increased obesity risk. Although these conditions commonly co-occur, shared factors relating to obesity risk are unknown. To examine the shared and unique associations of ADHD and autistic traits with eating behaviours and BMI. Children (N=4134) from the population-based Generation R Study were categorized into subgroups based on parent-reported ADHD and autistic traits scores at 6 years: ADHDHigh , ASDHigh , ADHD+ASDHigh and REF (reference group: ADHD+ASDLow ). Multiple linear regressions examined the associations between subgroups and eating behaviours (at 10 years) and BMIz (at 14 years), relative to REF. Mediation analyses tested the indirect effect of subgroup and BMIz through eating behaviours. ADHD + ASDHigh children expressed both food approach (increased food responsiveness and emotional overeating) and avoidant eating behaviours (increased emotional undereating, satiety responsiveness/ slowness in eating and picky eating, and decreased enjoyment in food). ASDHigh children were more food avoidant, while ADHDHigh children had more food approach behaviours and greater BMIz. ADHDHigh and BMIz were indirectly associated with food responsiveness and emotional overeating. ADHD and autistic trait phenotypes show distinct associations with potential obesity risk factors, and further research is needed to improve targeted early intervention.